Mass spectrometry will be utilized to develop automated methods for quantitative analysis and structure determination which are applicable to minimum quantity (10 to the minus 8th power - less than 10 to the minus 12th power g) samples of importance to biomedical and health-oriented problems. This supplemental application covers completion of a tandem double-focusing mass spectrometer in which ions can be separated at 50,000 mass resolution and their 30 kV collisional activation mass spectra obtained with a mass resolution of 5000. This instrument should have unique advantages for molecular structure determination, complex mixture analysis, and polypeptide sequencing.